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DL-FIND

	Summary			Lists			SCM			Files

DL-FIND

A geometry optimiser for quantum chemical and QM/MM calculations to be included into electronic structure codes. The code can be downloaded under "Files" as well as at the bottom of this page.

The citation for DL-FIND is:

Johannes Kästner, Joanne M. Carr, Thomas W. Keal, Walter Thiel, Adrian Wander and Paul Sherwood, J. Phys. Chem. A, 2009, 113 (43), 11856–11865.

DOI: 10.1021/jp9028968

Functionalities

Coordinate systems:

Cartesians (including frozen atoms and components)
Internals (including all constraints):
- DLC (delocalised internal coordinates)
- DLC-TC (total connection)
- HDLC
- HDLC-TC

Combinations of coordinates (images):

NEB (nudged elastic band)
Dimer method

All of the combinations work with all versions of coordinate systems.

Optimisers:

steepest descent
conjugate gradient
Newton-Raphson/quasi-Newton
L-BFGS
P-RFO, Hessian update mechanisms: Powell and Bofill. Hessian either by input or by finite-difference. In the latter case either in Cartesians (then the update also in Cartesians, and one can output frequencies), or in internals.
Damped dynamics

Line search algorithms:

Simple scaling of the proposed step (covering the maximum step length)
Trust radius based on energy decrease
Trust radius based on the projection of the gradient on the step

Conical intersection optimisations:

Penalty function
Gradient projection
Lagrange-Newton

Parallel search:

Genetic algorithm
Stochastic search

Restart mechanism:

The optimiser is fully restartable.

Availability:

DL-FIND is released under the L-GPL license. A reasonably stable snapshot can be downloaded below. The most recent svn snapshot can be checked out as described under SCM above. You have to register with this site (CCPForge) in order to check it out. You do not have to join the project, though.

DL-FIND is also distributed with ChemShell and GAMESS-UK